The present invention relates to an elastic button apparatus and more particularly to a button apparatus that employs a complex elastic unit to generate a two-step punch for enhancing feedback capability and controllability of the button-pressing operation.
Scissors mechanisms are widely used in power mechanical structures. For instances, in heavy load applications, they are adopted in cranes or vertical elevators. In light-duty applications, the scissors mechanisms are also adopted in the button key structures of notebook computers or the like. FIG. 1 shows typically a button apparatus 1 adopted in notebook computers. The button apparatus 1 includes a base 10, a key top 11, an elevation mechanism 12 consisting of a dual-scissors mechanism for connecting the base 10 and the key top 11, and a rubber 13 located in the elevation mechanism 12 (between the two scissors mechanism). The rubber 13 is used to provide resilience for the button-pressing operation.
In conventional techniques, the button apparatus mentioned above usually have an elastic element (such as the rubber 13) to store potential energy and function as a returning mechanism. Such a type of element generally has a fixed elasticity coefficient. Hence, within the application range of the elastic element, a definite elastic relationship between the resilience and the deformation can be provided (as shown by the pattern I in FIG. 2). However, such a simple relationship between the deformation and the resilience sometimes cannot meet the requirements of actual applications. Hence, in some conventional techniques, in order to support larger loads or change the single resilience pattern, it is a common practice to couple elastic elements of different elasticity in parallel to form a relationship between the deformation and the resilience as the one shown by Pattern II in FIG. 2.
Analysis of the relationship between the deformation and the resilience shown by the pattern II in FIG. 2 indicates that a greater deformation can generate a greater loading support or a greater resilience. Though such an application is usually adopted for heavy-duty apparatus such as cranes, yet it hasn""t been found in light-duty apparatus such as the button apparatus of notebook computers.
As mentioned above, in the light-duty apparatus, the elastic mechanism of the Pattern II has not been adopted. However, in terms of control and manufacturing, the two-step resilience can provide substantial advantages for those light-duty apparatus, especially for the button apparatus of notebook computers. As the button apparatus is by nature to receive the pressing or hitting impact of users. The construction employing the pattern of two-step resilience enables users to get a better punch feeling (i.e. feedback sense). It helps users to get better control during striking operations. Moreover, from the standpoint of the users of the keyboard, they usually place their fingers on the button keys in advance. The construction employing the pattern of two-step resilience enables users to avoid the risk of xe2x80x9cfault-strikingxe2x80x9d.
Nevertheless, to make the button apparatus according to the Pattern II shown in FIG. 2 has two drawbacks. Firstly, the controllability of pressing is not desirable. Secondly, user""s fatigue resulting from hitting the button keys tends to accumulate in an accelerating manner. The poor controllability is caused by a greater force required to apply to the button key for generating a preset deformation (as shown by Pattern II in FIG. 2, in which the resilience increases as the deformation increases). Hence, the control feedback sense of pressing operations by steps is not adequate. The acceleration of user""s fatigue is caused by the greater force required in the operations (comparing Pattern I with Pattern II in FIG. 2) to reach the preset deformation. As pressing operations take place frequently (for instance, for a user to enter 60 Chinese characters per minute, with one Chinese character requiring average four strikes on the button keys, the user has to strike the keyboard 240 times a minute, or 14400 times an hour). Hence, even a small increase of operation force does affect user""s operation continuity, or even result in impact occupational injury.
Therefore, to provide an improved two-step elastic mechanism for small loading button, apparatus such as notebook computers is an important target deserved pursuing.
The primary object of the invention is to provide an elastic button apparatus that employs a complex elastic unit for enabling users to operate with two-step resilience so as to enhance feedback sense and controllability.
The elastic button apparatus of the invention includes a base, a key top, an elevation mechanism and a complex elastic unit. The key top is located above the base. The elevation mechanism is located between the base and the key top for guiding lifting and lowering operations of the key top. The complex elastic unit is located also between the key top and the base to provide resilience to the button apparatus to perform lifting and lowering operations. The complex elastic unit includes a lower elastic element located on the base and an upper elastic element located below the key top. While the elastic button apparatus is lifting or lowering, the complex elastic unit generates an S-shaped resilience pattern through the compression of the upper elastic element and the lower elastic element, in response to the decrease of the spacing between the key top and the base.
In the invention, the elevation mechanism employed in the elastic button apparatus may be a scissors mechanism.
In one embodiment of the invention, the lower elastic element may be a conical rubber with the convex side pointing upwards or a conical metal cape with the convex side pointing upwards.
In one embodiment according to the one set forth above, the upper elastic element corresponding to the lower elastic element may be a pair of repulsive magnets located on a bottom side of the key top and a top end of the lower elastic element, respectively.
In one embodiment according to the one set forth above, the upper elastic element corresponding to the lower elastic element may be a pair of repulsive magnets located on a bottom side of the key top and a bottom end of the lower elastic element, respectively.
In another embodiment according to the one set forth above, the upper elastic element may be a conical rubber with the convex side facing downwards, a conical metal cape with the convex side facing downwards, a compression spring or an elastic element of the like.
In another embodiment of the invention, the upper elastic element may be a conical rubber with the convex side facing downwards or a conical metal cape with the convex side facing downwards.
In one embodiment according to the one set forth above, the lower elastic element corresponding to the upper elastic element may be a pair of repulsive magnets located on the base and a bottom end of the upper elastic element, respectively.
In one embodiment according to the one set forth above, the lower elastic element corresponding to the upper elastic element may be a pair of repulsive magnetic elements located on the base and a top end of a bottom section of the upper elastic element, respectively.
In another embodiment according to the one set forth above, the lower elastic element may be a conical rubber with the convex side facing upwards, a conical metal cape with the convex side facing upwards, a compression spring or an elastic element of the like.
The elastic button apparatus of the invention may be adapted on keyboards or devices with like button structures. For instances, when the elastic button apparatus is directly used on a keyboard, the keyboard includes a base and a plurality of elastic button apparatus located on the base.
The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.